From ccf970c7a77e86f4f5ef8ecc5e637114b1c0136a Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Fri, 15 Sep 2017 11:31:13 -0300 Subject: posix: Add compat glob symbol to not follow dangling symbols This patch follows commit 5554304f0 (posix: Allow glob to match dangling symlinks [BZ #866]) by adding a compat symbol that follow previous semantic of not following dangling symlinks and thus avoiding call gl_lstat with GLOB_ALTDIRFUNC. It avoids failure with old binaries that not set the alternate function pointer for lstat (GNUmake for instance). The following scenario, for instance, fails with current GNUmake because glibc will access unitialized memory when calling gl_lstat: $ cat src/t/t.c int main () { return 0; } $ cat Makefile SRC = $(wildcard src/*/t.c) OBJ = $(patsubst src/%.c, obj/%.o, $(SRC)) prog: $(OBJ) $(CC) $(CFLAGS) $(LDFLAGS) $(LIBS) $(OBJ) -o prog obj/%.o: src/%.c $(CC) $(CFLAGS) -c $< -o $@ $ make This works as expected with the patch applied. Since it is for generic ABI, default compat symbols are added with override for Linux due LFS. Now we have two compat symbols for glob on Linux: 1. sysdeps/unix/sysv/linux/oldglob.c which implements glob64 with the old dirent layout. For this implementation I also set it to not follow dangling symlinks (which is the safest path). 2. sysdeps/unix/sysv/linux/glob{64}-lstat-compat.c which implements the compat symbol for dangling symlinks. As for generic glob, the implementation uses XSTAT_IS_XSTAT64 to define whether both __glob_lstat_compat and __glob64_lstat_compat should be different implementations. For archictures that define XSTAT_IS_XSTAT64, __glob_lstat_compat is aliased to __glob64_lstat_compat. 3. sysdeps/unix/sysv/linux/alpha/oldglob.c with a different glob_t layout. As for 1. this patch changes it to not follow dangling symlinks. The patch also bumps _GNU_GLOB_INTERFACE_VERSION to 2 to advertise the new semantic. On GNUmake, for instance, it will force to it use its internal glob implementation instead and avoiding triggering the same failure on builds against newer GLIBCs. Checked on x86_64-linux-gnu and i686-linux-gnu. I also checked with a build against the major ABIs required to check for the abilist. The changes should also work on gnulib (I run gnulib-tool.py check glob and it shown no regressions). [BZ #22183] * include/gnu-versions.h (_GNU_GLOB_INTERFACE_VERSION): Increase version to 2. * posix/Makefile (routines): Add glob-lstat-compat and glob64-lstat-compat. * posix/Versions (GLIBC_2.27, glob, glob64): Add symbol version. * posix/glob-lstat-compat.c: New file. * posix/glob64-lstat-compat.c: Likewise. * posix/tst-glob_lstat_compat.c: Likewise. * sysdeps/unix/sysv/linux/glob-lstat-compat.c: Likewise. * sysdeps/unix/sysv/linux/alpha/glob-lstat-compat.c: Likewise. * sysdeps/unix/sysv/linux/glob64-lstat-compat.c: Likewise. * sysdeps/unix/sysv/linux/alpha/glob.c: Remove file. * posix/glob.c (glob_lstat): New function. (glob): Rename to __glob and add versioned symbol to 2.27. (glob_in_dir): Use glob_lstat. * posix/glob64.c (glob64): Add GLOB_ATTRIBUTE. * sysdeps/unix/sysv/linux/arm/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/glob.c (glob): Add versioned symbol for 2.27. * sysdeps/unix/sysv/linux/glob64.c (glob64): Likewise. * sysdeps/unix/sysv/linux/oldglob.c (GLOB_NO_LSTAT): Define. * sysdeps/unix/sysv/linux/alpha/oldglob.c (__old_glob): Do not use gl_lstat on glob call. * sysdeps/unix/sysv/linux/aarch64/libc.abilist: Add GLIBC_2.27 glob and glob64 symbols. * sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist: Likewise. * sysdeps/unix/linux/powerpc/powerpc32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise. --- include/gnu-versions.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/gnu-versions.h b/include/gnu-versions.h index 40f2bfc..ce26254 100644 --- a/include/gnu-versions.h +++ b/include/gnu-versions.h @@ -45,7 +45,7 @@ #define _GNU_OBSTACK_INTERFACE_VERSION 1 /* vs malloc/obstack.c */ #define _GNU_REGEX_INTERFACE_VERSION 1 /* vs posix/regex.c */ -#define _GNU_GLOB_INTERFACE_VERSION 1 /* vs posix/glob.c */ +#define _GNU_GLOB_INTERFACE_VERSION 2 /* vs posix/glob.c */ #define _GNU_GETOPT_INTERFACE_VERSION 2 /* vs posix/getopt.c and posix/getopt1.c */ -- cgit v1.1